Apparatus for drilling wells



L. A. MARTINI APPARATUS FOR DRILLING WELLS Nov. 27, 1962 2 Sheets-Sheet 1 Filed Dec. 15, 1958 INVENTOR Leo A. Martini MKM ATTORNEY L. A. MARTINI APPARATUS FOR DRILLING WELLS Nov. 27, 1962 2 Sheets-Sheet 2 Filed Dec. 15, 1958 Tf/Z/v INVENTOR Leo A. Martin i @KW Fig.3-A

ATTORNEY 3,%5,8fl Patented Nov. 27,1962

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3,965,805 APPARATUS FOR DRILLING WELLS Leo A. Martini, 5322 Cedar Springs Road, Dallas, Tex. Filed Dec. 15, 1953, Ser. No. 780,354 4 Claims. (Cl. 175-56) This invention relates to apparatus for drilling Wells, and it concerns more particularly hydraulic means, operable by pressure and inertia of a drilling fluid, for imparting a vibratory movement to a drilling bit, and has reference to the disclosures set forth in an application filed by me on February 6, 1957, and bearing Serial No. 638,- 652, now Patent No. 2,905,439.

An object of the invention is to provide, in well drilling apparatus including a drill pipe and a drilling bit con nected to the drill pipe and rotatable therewith, the drill pipe and the drilling bit providing a continuous fluid passage for introducing a drilling fluid into a well bore adjacent the bottom thereof, hydraulic means responsive to the pressure of the drilling fluid for imparting a vibratory movement to the bit during rotation thereof.

Anotherobject of the invention is to provide a structure as described in which the valve is adapted to be seated in response to pressure of the drilling fluid, and in whichthe valveapproaches the valve seat more rapidly as it is advanced in close proximity thereto, and is seated abruptly, whereby the increased pressure of the drilling fluid imparts a vibratory movement to the drilling bit.

Another object of'the invention is to provide a structure as described in which pressure builds up in the inner cylinder below the piston upon seating of the valve, to thereby raise the piston and disengage the valve from its seat, the arrangement being such that the valve is' continually opened and closed in response to pressure and inertia of the drilling fiuid, whereby an intermittent vibratory movement is imparted to the drilling bit, through the casing.

. Broadly, the invention contemplates the provision of drilling apparatus embodying features of construction by which, as the drilling bit progresses downwardly, a 1ongitudinal vibratory action is transmitted thereto by the intermittent interruption of the flow of drilling fluid through the drill pipe.

The invention will be readily understood by referring to the following description and the accompanying drawing, in which:

FIGURE 1 is a diagrammatic elevational view showing apparatus embodying the invention operatively connected to a drill pipe and a drilling bit disposed in a well bore;

FIGURES 2 and 2A together comprise a single elevational view on an enlarged scale, partly in section taken on a median line, of a portion of the apparatus shown in FIGURE 1;

FIGURES 3 and 3A together comprise a single view similar to that of FIGURES 2 and 2A, showing a modified form of the invention;

FIGURE 4. is a sectional plan view, on an enlarged scale, taken on the line 4-4 of FIGURE 3;

FIGURE 5 is a sectional plan view, on an enlarged scale, taken on the line 5-5 of FIGURE 3A; and

FIGURE 6 is a sectional plan view, on an enlarged scale, taken on the line 66 of FIGURE 3A.

Referring to FIGURE 1 of the drawing, the numeral 1 designates a well bore. A drill pipe, indicated generally by the numeral 2, is disposed in the Well bore 1. A drilling bit, which may be of any suitable construction and is indicated generally by the numeral 3, is connected to the lower end of the drill pipe 2 and is rotatable therewith. In accordance with the usual practice, the drill pipe 2 and the drilling bit 3 provide a continuous fluid 2 passage for introducing a drilling fluid into the well bore 1 adjacent the bottom thereof.

The apparatus of ths invention includes a cylindrical casing, as hereinafter described, which is connected between the drill pipe 2 and the drilling bit 3 and provides a fluid passage therebetween. The casing has a first sec-- tion 4, which is connected to the drill pipe 2, and a second section 5, which is connected to the drilling bit 3.

As shown in FIGURES 2 and 2A, the second casing section 5 is connected to the drilling bit 3 by threads, and is received telescopically in the first casing section 4, to which it is connected by threads 7. The second casing section 5 has a central bore 8 which is in fluid communication with discharge ports 9 formed in the drilling bit 3.

A valve seat It which is preferably formed of resilient material, is positioned in the upper end of the bore 8. A cylindrical valve cage 11 is connected to the second casing section 5, by threads 12, and extends upwardly therefrom. A ball valve 13, which has a resilient covering 14, is disposed in the valve cage 11 and is engageable with the valve-seat 10. The valve 13 has a stem 15 extending upwardly therefrom.

An inner cylinder 16 is connected to the valve cage 11, by threads 17, and extends upwardly therefrom. The valve cage 11 and the inner cylinder 16 are of lesser diameter than the first casing section 4 to provide an annular fluid passage 18 therearound. The valve cage 11 has a restricted orifice l9 surrounding the valve stem 15 and communicating with the interior of the inner cylinder 16, and has side openings 20 communicating with the annular fluid passage 18.

The valve cage 11 has an upwardly and radially outwardly tapered surface 21 surrounding the orifice l9, and has an upstanding marginal flange 22 which is spaced inwardly from the inner wall of the cylinder 16. The cage 11 may not necessarily be conical in form, as defined by the tapered surface 21 thereof, and the size of the orifice 19 may vary according to the requirements.

A piston 23, which is disposed in the inner cylinder 16- and normally rests on the upstanding marginal flange 22 of the valve cage 11, has a central opening 24 surround-- ing the valve stem 15. The opening 24 is enlarged at its upper end to form a spring seat 25. A coil spring 26, p

which surrounds the valve stem 15 and is received in the spring seat 25, extends upwardly above the piston 23 for engagement with the enlarged upper end 27 of the valve stem 15. The spring 26 acts on the valve stem 15 and thepiston 23 to bias the valve stem 15 upwardly relative to the piston 23 whereby the valve 13 is normally disengaged from the valve seat 10.

In operation, the valve 13 is adapted to be seated in response to pressure of the drilling fluid. The valve 13 approaches the valve seat 10 more rapidly as it is advanced in'close proximity thereto, and is seated abruptly, whereby a vibratory movement is imparted to the drilling bit 3, through the casing.

Pressure builds up in the inner cylinder 16 below the piston 23 upon seating of the valve 13, to thereby raise the piston 23 and disengage the valve 13 from the valveseat 10. The arrangement is such that the valve 13 is continually opened and closed in response to pressure of the drilling fluid, whereby a vertical vibratory movement is imparted to the drilling bit 3, through the casing.

a A cylindrical cover 28, which encloses the upper ends of the valve stem 15 and the spring 26 and limits the upward movement of the valve stem 15, has a radially outwardly extending peripheral flange 29' which is connected to the upper surface of the piston 23 by screwswhich is secured to the under side of the piston 23 by Screws 35.

An annular support 36, which has a central opening, extends radially inwardly from the inner cylinder 16 intermediate its ends. A coil spring 37, which is substantially larger than the spring 26, is positioned in the inner cylinder 16, below the annular support 36, and surrounds the cover 28. The spring 37 acts on the piston 23 and the annular support 36 to bias the piston 23 downwardly in the inner cylinder 16 to thereby resist upward movement of the valve stem, to disengage the valve 13 from its seat, in response to pressure of the drilling fluid acting on the under side of the piston 23.

A piston 38 is positioned in the inner cylinder 16 above the annular support 36 and normally rests thereon. The space in the inner cylinder 16 between the pistons 23 and 38 is normally filled with oil, and the piston 38 is freely movable in the inner cylinder 16 in response to differences of fluid pressure above and below it. The cover 28 has a fluid port 39 in the wall thereof whereby the space enclosed by the cover 28 is filled with oil also. An annular member or plug 40, which partially closes the upper end of the inner cylinder 16, is secured therein by threads 41. A coupling member 42 is connected to the upper end of the first casing section 4, above the inner cylinder 16, by threads 43. The coupling member 42 has an integral tubular portion 44 concentrically thereof which depends from a partition 45 intermediate the ends of the coupling 42 through the plug 40 in sliding engagement with the latter. A pair of resilient O-rings 46 are received in annular grooves provided therefor in the annular member 40 for sealing engagement with the tubular portion 44.

The upper end of the tubular portion 44 is closed, and the partition 45 has longitudinally and radially extending passages 47 and 48 therein. The longitudinally extending passages 47 communicate with the annular fluid passage 18, and the radially extending passages 48 communicate with corresponding openings 49 and 50 in the walls of the coupling member 42 and the tubular portion 44, respectively, whereby the interior of the inner cylinder 16, adjacent its upper end, is in fluid communication with the well bore 1.

A coupling member 51 is connected at its ends, by threads 52 and 53, to the drill pipe 2 and the coupling member 42. The coupling member 51 has a central bore 54 communicating at one end with the interior of the drill pipe 2. The opposite end of the bore 54 is tapered downwardly and outwardly, as at 55, and communicates with the longitudinally extending passages 47 of the partition 45 of the coupling member 42.

The arrangement shown in FIGURES 3 and 3A ineludes the following features which are not shown in FIGURES 2 and 2A:

A portion of the peripheral surface of the second casing section below the valve cage 11 is splined, as at 56, and the first casing section 4 has a correspondingly splined internally enlarged portion 57 opposite the splined surface 56 of the second casing section 5 for slidable interlocking engagement therewith, whereby the second casing section 5 is positively secured to the first casing section 4 for rotative movement therewith while at the same time the second casing section 5 is capable of a limited longitudinal movement relative to the first casing section 4.

The lower end of the valve cage 11 forms a shoulder for abutment against the internally enlarged portion 57 of the first casing section 4 to limit downward movement of the second casing section 5 relative to the first casing section 4. The second casing section 5 has an external shoulder 58 for abutment against the lower end of the first casing section 4 to limit upward movement of the second casing section 5 relative to the first casing section 4.

The invention may be modified in various ways without departing from the spirit and scope thereof.

What is claimed is:

1. In well drilling apparatus including a drill pipe and a drilling bit connected to the drill pipe and rotatable therewith, the drill pipe and the drilling bit providing a continuous fluid passage for introducing a drilling fluid into a well bore adjacent the bottom thereof, hydraulic means responsive to the pressure of the drilling fluid for imparting a vertical vibratory movement to the bit during rotation thereof, the hydraulic means including a cylindrical casing connected between the drill pipe and the drilling bit and providing a fluid passage therebetween, the casing having a first section connected to the drill pipe and a second section connected to the drilling bit, the second casing section being received telescopically in the first casing section and having a central bore, a valve seat in the upper end of the bore, a cylindrical valve cage connected to the second casing section and extending upwardly therefrom, a ball valve in the valve cage engageable with the valve seat, the valve having a stem extending upwardly therefrom, an inner cylinder connected to the valve cage and extending upwardly therefrom, the valve cage and the inner cylinder having a lesser diameter than the first casing section to provide an annular fluid passage therebetween, the valve cage having a restricted orifice near its upper end surrounding the valve stem and communicating with the interior of the inner cylinder, and having side openings communicating with the annular fluid passage, a piston in the inner cylinder surrounding the valve stem and normally resting on the valve cage, above the restricted orifice, a coil spring surrounding the valve stem and acting on the valve stem and the piston to bias the valve stem upwardly relative to the piston whereby the valve is normally disengaged from the valve seat, and a second coil spring in the inner cylinder above the piston acting on the piston and the inner cylinder to bias the piston downwardly in the inner cylinder to thereby resist upward movement of the valve stem to disengage the valve from its seat in response to pressure of the drilling fluid acting on the under side of the piston, the arrangement being such that the valve is adapted to be seated in response to pressure of the drilling fluid, the valve approaches the valve seat more rapidly as it is advanced in close proximity thereto, and is seated abruptly, and pressure builds up in the inner cylinder below the piston upon seating of the valve, to thereby raise the piston and disengage the valve from its seat, the valve being continually opened and closed in response to pressure of the drilling fluid, whereby a vibratory movement is imparted to the drilling bit through the casing.

2. The structure of claim 1, an annular support extending radially inwardly from the inner cylinder intermediate its ends, a second piston in the inner cylinder above the annular support and normally resting thereon, the space in the inner cylinder between the pistons normally being filled with a non-compressible fluid, the second piston being freely movable in the inner cylinder in response to differences of fluid pressure above and below it, an annular member partially closing the upper end of the inner cylinder, a coupling member connecting the first casing section to the drill pipe, the coupling member having a partition intermediate its ends and having an integral tubular portion arranged centrally thereof and depending into the inner cylinder, a plug threaded into the inner cylinder having a central bore receiving the tubular portion, the upper end of the tubular portion being closed and the partition having longitudinally and radially extending passages therein, the longitudinally extending passages communicating with the annular fluid passage and the radially extending passages communicating with corresponding openings in the walls of the coupling member and the tubular portion, and a second coupling member connected between the first mentioned coupling member and the drill pipe, the second coupling member having a central-bore communi eating at one end with the interior of the drill pipe, the opposite end of the last mentioned bore being tapered downwardly and outwardly and communicating with the longitudinally extending passages of the partition of the first mentioned coupling member.

3. The structure of claim 2, a portion of the peripheral surface of the second casing section below the valve cage being splined and the first casing section having a correspondingly splined internally enlarged portion opposite the splined surface of the second casing section, for interlocking, sliding engagement therewith whereby the second casing section is positively secured to the first casing section for rotative movement therewith, while at the same time the second casing section is capable of a limited longitudinal movement relative to the first casing section, the lower end of the valve cage forming a shoulder for abutment against the internally enlarged portion of the first casing section to limit downward movement of the second casing section relative to the first casing section and the second casing section having an external shoulder for abutment against the lower end of the first casing section to limit upward movement of the second casing section relative to the first casing section.

4. A drilling tool for intermittently increasing the downward pressure on a drill bit on a drill string at the bottom of a subterranean bore, having telescopically connected upper and lower tubular sections and having said bit rigidly connected to said lower section, and fluid passages in said sections open to said bit, the improvements comprising, a valve seat in the fluid passage in said lower section, a valve cage arranged in said lower section above said seat having a pluarality of elongated openings providing communication between said sections, and having a central orifice thereabove, the said cage defining a chamber thereabove in said lower section, a valve in said cage engageable with said seat and a stern for said valve arranged through said orifice, a spring biased piston in said chamber embracing said stern, and means forming a part of said piston providing yieldable connection thereof with said stem.

References Cited in the file of this patent UNITED STATES PATENTS 1,892,517 Pennington Dec. 27, 1932 2,746,721 Moore May 22, 1956 2,758,817 Bassinger Aug. 14, 1956 2,774,334 Cline Dec. 18, 1956 2,859,733 Bassinger et a1. Nov. 11, 1958 2,905,439 Martini Sept. 22, 1959 

